Pavlica Matic, Kržan Mojca, Nemec Ana, Kosjek Tina, Baš Anže, Seliškar Alenka
Small Animal Clinic, Veterinary Faculty, University of Ljubljana, 1000 Ljubljana, Slovenia.
Department of Pharmacology and Experimental Toxicology, Faculty of Medicine, University of Ljubljana, 1000 Ljubljana, Slovenia.
Animals (Basel). 2022 May 9;12(9):1217. doi: 10.3390/ani12091217.
This study investigated the cardiopulmonary effects and pharmacokinetics of dexmedetomidine (DEX) used as an adjunctive analgesic for regional anesthesia of the oral cavity with levobupivacaine in anesthetized dogs. Forty dogs were randomly assigned to four groups of 10 dogs. All dogs received levobupivacaine (4 blocks) with DEX IO (infraorbital block, = 10) or IA (inferior alveolar block, = 10) or placebo (PLC; = 10) or DEX ( = 10) was injected intravenously (IV) after administration of levobupivacaine. The dose of DEX was always 0.5 µg/kg. Cardiopulmonary parameters were recorded, and blood was drawn for the quantification of DEX in plasma using LC-MS/MS. Heart rate was lower in all LB + DEX groups, while mean arterial pressure (MAP) was higher in the LB + DEX IV and LB + DEX IA groups compared to the LB + PLC IV group. Compared to DEX IV, IO and IA administration resulted in lower MAP up to 2 min after application. Absorption of DEX was faster at IO administration (C and T were 0.47 ± 0.08 ng/mL and 7.22 ± 1.28 min and 0.76 ± 0.09 ng/mL and 7.50 ± 1.63 min for the IO and IA block, respectively). The IA administration resulted in better bioavailability and faster elimination (t was 63.44 ± 24.15 min and 23.78 ± 3.78 min for the IO and IA block, respectively). Perineural administration of DEX may be preferable because of the less pronounced cardiovascular response compared to IV administration.
本研究调查了右美托咪定（DEX）作为辅助镇痛药与左旋布比卡因联合用于麻醉犬口腔区域麻醉时的心肺效应和药代动力学。40只犬被随机分为4组，每组10只。所有犬均接受左旋布比卡因（4个阻滞部位），其中10只接受眶下神经阻滞（IO）联合DEX，10只接受下牙槽神经阻滞（IA）联合DEX，10只接受安慰剂（PLC），10只在给予左旋布比卡因后静脉注射（IV）DEX。DEX剂量始终为0.5μg/kg。记录心肺参数，并采集血液用液相色谱-串联质谱法（LC-MS/MS）定量血浆中的DEX。所有左旋布比卡因+DEX组的心率均较低，而与左旋布比卡因+PLC IV组相比，左旋布比卡因+DEX IV组和左旋布比卡因+DEX IA组的平均动脉压（MAP）较高。与静脉注射DEX相比，IO和IA给药后2分钟内MAP较低。DEX在IO给药时吸收更快（IO阻滞和IA阻滞时的Cmax和Tmax分别为0.47±0.08 ng/mL和7.22±1.28分钟以及0.76±0.09 ng/mL和7.50±1.63分钟）。IA给药导致更好的生物利用度和更快的消除（IO阻滞和IA阻滞时的t1/2分别为63.44±24.15分钟和23.78±3.78分钟）。与静脉给药相比，DEX神经周围给药可能更可取，因为其心血管反应不太明显。
